Finally

[Kevin Alexander]

Be sure also to set the parallax on that scope for your eye. If I recall the instructions said if you set it at the 300 yds, it would be good for all distances. If it's not set for your eye, that can cause huge groups.
I like Cartridge in some cases it's very hard to find a more accurate load, but it almost always gives considerable less velocity.
What twist does your 40-70 have?

1 in 14 twist.